Multiuser Detection in MC-CDMA Communication Systems Using MPEM Algorithm

In this paper, we propose a sub-optimum multiuser detection technique in multicarrier code division multiple access (MC-CDMA) communication systems based on missing parameter expectation maximization (MPEM) algorithm. In the proposed detection procedure, first initial values for the bits of all users are estimated from received signal. Then, the proposed MPEM based algorithm uses outputs of carries' demodulators to improve the accuracy of the initial estimates of the bits. In this paper, the expectation and maximization steps' functions of the MPEM algorithm for MC-CDMA multiuser detection are derived and the performance of the proposed algorithm is analyzed. Our presented numerical results demonstrate the efficiency of the proposed detection algorithm both in bit error rate performance and computational complexity points of view.